Aerobic exercise, such as running and cycling, basically reduces body fat. The best way to lose weight is sit-ups. In the gym, I also saw an instrument, which is also a sit-up type. That key doesn't hurt your waist. You think sit-ups are ineffective. Maybe you're asking too much. I tell you, if you do 5-7 groups a day, I don't believe you can lose weight. Even thin people can lose half a catty. You have no place to exercise, so you are here.